At present, the main structures on White Tower Crag are a trig point (NS3974 : Trig point on Dumbarton Rock), a flagstaff, and the toposcope (or topograph: these indicate directions and distances to various points of interest) that appears in this photo, partly enclosed by the ruined semicircular base of a building. (The foreshore area at Levengrove is visible in the background, behind the pillar.)

Early in the site's history, when the Rock served as the fortress of the Strathclyde Britons, "the western of the two peaks, the White Tower Crag, would have been too pointed for anything other than a look-out post" [HD, p11, 71].

In the medieval period, several buildings were clustered in the level terrace between the two peaks (the Over Bailey – see Link ). However, the western peak was the location of the White Tower, a watch-tower which gave the crag its modern name (the identification as a watch-tower is from [HD, p73]); it was apparently at, or close to, the location of the modern direction indicator shown in this image.

The White Tower is shown in John Slezer's view (c. 1690) of the Rock from the north-west [HD, p74], and is mentioned even earlier, in a 1580 inventory [MacPhail, p132]. However, that tower has been completely destroyed; the ruined semicircular base that is currently visible here is of unknown origin [OSG07, p5].